Bonded Contact- Separation
 

Hi,

I have to do the modal analysis of a sandwich plate (can be considered as honeycomb plate) (IMG 1). The top & bottom sheets are thin & made of isotropic material. The middle sheet is made of orthotropic material. The contact definition between layers are defined as bonded. (IMG 5)

The outer surface of one the sheet is fixed (boundary condition). I have left all other options as default.

With these settings, the obtained mode shapes show separation / penetration among the layers of plate. (IMG 2/3).


If I change the formulation as MPC, both top & bottom sheet becomes fixed & only middle sheet deforms, which is wrong. (IMG 4)

Plz let me know, what options should I select to ensure bonded connection between these layers.


Images:
https://ibb.co/niPx85

https://ibb.co/gBqFvk

https://ibb.co/nOWNak

https://ibb.co/cjsjo5

https://ibb.co/mkkR1Q